Have gone back to City of the Sun God for the tremors storyline; currently on Tier 1/5 of Appeasing the Flame. Was in Le Creux looking, wall hug right more or less, searching the area for a ring. Clicked on one of the portal stabilizer things first introduced around the Overlook Hotel in Savage Coast. Then clicked on the nearby portal. Bad move. Portal zoned me into an instance that was clearly not for the quest I’m on; defeated jinn leave a glowly blue thing that does nothing when clicked. Cleared the area of all mobs; no way to zone back out. /reset puts me back in again. Had to teleport.
tl;dr can click a portal into a mission area (?) that there’s no escape from if you weren’t on the correct quest. Maybe portal should only be usable if on the quest?